Which of the following aminoglycosides requires careful timing for specimen collection?

Gentamicin is an aminoglycoside antibiotic that is known for its efficacy against serious infections caused by gram-negative bacteria. The timing of specimen collection for gentamicin is crucial because its therapeutic window is narrow; this means there is a fine line between an effective dose and a potentially harmful dose. Timing helps to ensure that drug levels are measured accurately, allowing healthcare providers to adjust dosages based on whether the levels are too high (risking toxicity) or too low (risking treatment failure).

Monitoring gentamicin levels typically involves measuring peak and trough levels. Peak levels should be measured after the drug has been administered to ensure that it reaches an effective concentration in the bloodstream, while trough levels are collected just before the next dose to confirm that the drug is at a therapeutic but not toxic level.

On the other hand, the other medications listed—amoxicillin, penicillin, and ciprofloxacin—do not require the same level of precision in timing for specimen collection. While monitoring may be necessary for these antibiotics as well, they typically have different pharmacokinetic profiles that do not necessitate the strict timing requirements seen with gentamicin.